Saint-Denis
Reunion
Long-term weather forecast
Long-term weather forecast

September weather forecast and climate
Saint-Denis, Reunion

An aerial panoramic shot of the glorious landscape of the Saint-Denis city, on Reunion Island
An aerial panoramic shot of the glorious landscape of the Saint-Denis city, on Reunion Island
The first month of the spring, September, is also a moderately hot month in Saint-Denis, Reunion, with average temperature varying between 18.6°C (65.5°F) and 25.8°C (78.4°F).

Temperature

In Saint-Denis, Reunion, the average high-temperature in September is relatively the same as in August - a still moderately hot 25.8°C (78.4°F). The average low-temperature, in Saint-Denis, is 18.6°C (65.5°F).

Rainfall

In Saint-Denis, Reunion, it is raining for 8.1 days, with typically 50mm (2") of accumulated precipitation. Throughout the year, there are 119.3 rainfall days, and 1658.6mm (65.3") of precipitation is accumulated.

Sea temperature

Months with the coldest seawater are August and September, with an average sea temperature of 23.8°C (74.8°F). Depending on a person's sensitivity to cold, with regards to sunshine, wind, and air temperature, a quick swim in 23.8°C (74.8°F) water may be enjoyable. (FYI: The official water temperature required for the Olympic swimming competition is 25°C (77°F) to 28°C (82.4°F).)

Daylight

In Saint-Denis, the average length of the day is 12h.

Sunshine

In September, the average sunshine in Saint-Denis is 7.1h.

UV index

In September, the average daily maximum UV index is 10. A UV Index of 8 to 10 symbolizes a very high health hazard from the exposure to the Sun's UV radiation for the ordinary person.
The average daily UV index of 10 transform into the following instructions:
Take special precautions, as unprotected skin can be damaged and can burn quickly. Seek shade and minimize exposure to direct Sun in a period between 10 a.m. and 4 p.m. when UV radiation is most intense; keep in mind that shade structures like parasols or canopies do not provide perfect sun protection. Sun-protective clothing, a long-sleeved shirt and pants, a wide-brimmed hat, and UVA and UVB-blocking sunglasses are particularly helpful in blocking UV radiation's harmful effects. Protect yourself by liberally applying a sunscreen of at least 30 SPF. Sunscreen prevents sunburn and decreases the damaging effects of Sun's radiation on the immune system. Beware! The strength of the UV rays is significantly increased by the reflection of the water and sand.

What is the temperature in September in Saint-Denis?

The average high-temperature, in September, in Saint-Denis, Reunion, is 25.8°C (78.4°F), while the average low-temperature is 18.6°C (65.5°F).

How much does it rain in Saint-Denis in September?

In Saint-Denis, in September, during 8.1 rainfall days, 50mm (2") of precipitation is typically accumulated.

What are the months with the coldest sea water in Saint-Denis?

August and September, with an average sea temperature of 23.8°C (74.8°F), are months with the coldest seawater. Depending on a person's sensitivity to cold, with regards to sunshine, wind, and air temperature, a quick swim in 23.8°C (74.8°F) water may be enjoyable.

What is the water temperature in September in Saint-Denis?

In September, the average sea temperature in Saint-Denis is 23.8°C (74.8°F). A person's cold intolerance, with sunshine, wind, and air temperature, are essential factors for enjoying swimming in 23.8°C (74.8°F) water.

How many hours of daylight does Saint-Denis have in September?

In September, the average length of the day in Saint-Denis is 12h.

How long on average sun shines in September in Saint-Denis?

In September, the average sunshine is 7.1h.

What is the UV index intensity in September in Saint-Denis?

In September, the average daily maximum UV index in Saint-Denis is 10. A UV Index of 8 to 10 symbolizes a very high health risk from unsafe exposure to the Sun's UV rays.
Average temperature in September - Saint-Denis, Reunion
  • Average high temperature in September: 25.8°C

Warmest months (with the highest average high temperature) are January and February (30.1°C).
The month with the lowest average high temperature is July (25.2°C).

  • Average low temperature in September: 18.6°C

The month with the highest average low temperature is February (23.7°C).
The coldest month (with the lowest average low temperature) is August (18°C).

Average rainfall in September - Saint-Denis, Reunion
  • Average rainfall in September: 50mm

The wettest month (with the highest rainfall) is February (351mm).
The driest month (with the lowest rainfall) is October (43.4mm).

Average rainfall days in September - Saint-Denis, Reunion
  • Average rainfall days in September: 8.1 days

The month with the highest number of rainy days is February (14.3 days).
The month with the lowest number of rainy days is November (5.9 days).

Average sea temperature in September - Saint-Denis, Reunion
  • Average sea temperature in September: 23.8°C

The best month for swimming (with the highest average sea temperature) is March (28.5°C).
Coldest months (with the lowest average sea temperature) are August and September (23.8°C).

Average daylight in September / Average sunshine in September - Saint-Denis, Reunion
  • Average daylight in September: 12h

The month with the longest days is December (Average daylight: 13.4h).
The month with shortest days is June (Average daylight: 10.9h).

  • Average sunshine in September: 7.1h

Months with most sunshine are April and December (Average sunshine: 7.4h).
Months with least sunshine are January and October (Average sunshine: 6.8).

Average UV index in September - Saint-Denis, Reunion
  • Average UV index in September: 10

Months with the highest UV index are January, February, March, November and December (UV index 12).
Months with the lowest UV index are June and July (UV index 6).